Artificial intelligence-based tumour infiltrating lymphocyte quantification in patients with triple-negative breast cancer: an independent validation study

An independent external validation (the CATALINA study) tested whether computational tumour-infiltrating lymphocyte scoring (cTIL) matches pathologist assessment in triple-negative breast cancer. Individual data were collated from 1759 patients pooled from seven randomised adjuvant trials, of whom 1356 had complete clinicopathological data. Both pathologist-read (sTIL) and computational scores were independently associated with invasive disease-free survival (HR 0.73, 95% CI 0.66–0.82 for sTIL and 0.80, 95% CI 0.73–0.89 for cTIL; q<0.0001). The authors state plainly that cTIL did NOT incrementally improve prognostication over models combining clinicopathological variables with pathologist scoring — they see the algorithm's role where routine pathologist assessment is unavailable.